1. Field
The exemplary embodiments relates to an acousto-optic element, an acousto-optic element array, and a display apparatus including the acousto-optic element. In particular, exemplary embodiments relate to an acousto-optic element capable of directing light in multiple directions, an acousto-optic element array, and a display apparatus including the acousto-optic element.
2. Description of the Related Art
An acousto-optic effect refers to the effect of changing optical characteristics of media using sound waves or ultrasonic waves. If light is incident on a medium changed in optical characteristics by the acousto-optic effect, the light is modulated according to the amount of change in the optical characteristics of the medium and is output from the medium. For example, the refractive index of a medium may be periodically changed by the acousto-optic effect so as to use the medium as a phase grating capable of diffracting light. In this case, the intensity or diffraction angle of light may be adjusted by changing the intensity or frequency of sound waves or ultrasonic waves applied to the medium. Thus, an optical modulator for modulating the amplitude of light or a scanner for deflecting light may be realized using the acousto-optic effect.
Research has been conducted on display technology using such optical modulators or scanners using the acousto-optic effect.
Related art binocular-parallax 3-dimensional image displays provide 3-dimensional images to viewers by generating left-eye and right-eye images having different viewpoints. Such 3-dimensional image displays may be classified into a glasses type and a non-glasses type.
Research into holographic 3-dimensional image displays has been conducted to provide more natural 3-dimensional images. Light may be considered as waves having intensity and phase, and holography is used to display 3-dimensional images by controlling the intensity and phase of light. Therefore, holographic 3-dimensional image displays include elements capable of controlling the amplitude (intensity) or phase of light.